Enginetech BC303J.020 is a 0.020 undersize main bearing set for 1961-1978 Ford, Mercury 5.8L-7.0L 351-428ci V8 engines.
Important Notes:
- Sized for crankshaft main journals machined .020 inch undersize. Measure journal diameter before installation - installing on the wrong journal size will cause immediate clearance failure.
- Always replace main bearings as a complete set. Never mix new bearings with used bearings - uneven wear and clearance differences will cause premature failure.
- With 3.824 diameter flange. Has grooved ID on upper & lower bearings.
- With 3.824 diameter flange. Has grooved ID on upper and lower bearings.
| Part Number | BC303J.020 |
| Bearing Size | 0.020 Undersize |
| Quantity Per Set | 5 main bearings per set |
| Engine | 5.8L-7.0L 351-428ci V8 |
| Year Range | 1961-1978 |
| Makes | Ford, Mercury |
| Country of Origin | IL |
| Weight | 1.5 lbs |
| UPC | 707473000000 |
| OEM Cross-Refs | ACL:5M685P, ACL:5M863P, FEL-PRO:4261M, King Engine Bearings:MB559AM, MAHLE:MS-685P |
Complete main bearing set covering all main journals for the V8 application - one set required per engine.
Fitment:
- 1961-1962 Ford Galaxie 6.4L 390ci V8
- 1961-1962 Ford Thunderbird 6.4L 390ci V8
- 1961-1962 Mercury Monterey 6.4L 390ci V8
- 1961-1963 Ford Country Sedan 6.4L 390ci V8
- 1961-1963 Ford Country Squire 6.4L 390ci V8
- 1961-1963 Ford Ranch Wagon 6.4L 390ci V8
- 1961-1963 Mercury Meteor 6.4L 390ci V8
- 1961-1965 Ford Fairlane 6.4L 390ci V8
- 1961-1967 Ford Galaxie 6.4L 390ci V8
- 1961-1967 Ford Thunderbird 6.4L 390ci V8
- 1961-1968 Ford Thunderbird 6.4L 390ci V8
- 1961-1968 Mercury Monterey 6.4L 390ci V8
- 1962-1963 Ford Galaxie 500 6.4L 390ci V8
- 1963-1963 Ford 300 6.4L 390ci V8
- 1963-1963 Mercury Country Cruiser 6.4L 390ci V8
- 1963-1965 Ford Galaxie 6.4L 390ci V8
- 1963-1965 Ford Thunderbird 6.4L 390ci V8
- 1963-1965 Mercury Monterey 6.4L 390ci V8
- 1963-1967 Ford Galaxie 6.4L 390ci V8
- 1963-1967 Ford Thunderbird 6.4L 390ci V8
- 1963-1967 Mercury Monterey 6.4L 390ci V8
- 1964-1964 Ford Galaxie 500 7.0L 427ci V8
- 1968-1968 Ford Galaxie 500 7.0L 427ci V8
- 1964-1964 Ford Galaxie 500 6.4L 390ci V8
- 1968-1971 Ford Galaxie 500 6.4L 390ci V8
- 1964-1965 Ford Thunderbird 7.0L 427ci V8
- 1964-1965 Mercury Caliente 7.0L 427ci V8
- 1964-1965 Mercury Colony Park 7.0L 427ci V8
- 1964-1965 Mercury Commuter 6.4L 390ci V8
- 1964-1965 Mercury Commuter 7.0L 427ci V8
- ...and 172 additional applications
Enginetech main bearings are engineered to OEM specifications, drawing on over 40 years of engine rebuilding expertise to deliver the precise clearance, crush, and eccentricity required for long-term durability under both stock and moderate-performance loads. Each set is application-specific: materials, wall thickness, oil clearance, and surface finish are all matched to the crankshaft main journal geometry and operating loads of the engine family it serves. Main bearings are a wear component and must be selected to match the crankshaft main journal size - bearings sized for standard journals will not seat correctly on undersize-machined journals and vice versa, so verify your journal measurement with a precision micrometer before ordering or installing. Always replace main bearings as a complete set. Mixing new bearings with used bearings produces uneven oil clearance across the crankshaft and accelerates wear on the freshly installed bearings - the small cost of a complete set is insurance against premature failure on the bearings you just paid to install. Enginetech documents every set with clear application-specific notes, journal-size designation, and cross-references so the right part lands on the bench the first time.
WARNING: This product can expose you to chemicals including lead and nickel, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
